Throttle configuration varying apparatus and control means therefor



May 3, 1960 A. E.,LEPLEY 2,935,295

THROTTLE CONFIGURATION VARYING APPARATUS AND CONTROL MEANS THEREFORFiled Jan. 26. 1951 fnVE'nt 0P i5 34 37 (Allen ELe gZe y THROTTLECONFIGURATION VARYING APPA- RA'I'US AND CONTROL MEANS THEREFOR Allen E.Lepley, Cleveland, Ohio, assignor to Thompson Ramo Wooldridge Inc., acorporation of Ohio Application January 26, 1951, Serial No. 207,980

9 Claims. (Cl. 253-52) This invention relates generally to a throttlestructure and more particularly to a nozzle inlet of a turbine havingmeans to control a variable inlet area in response to operatingconditions, thereby to selectively throttle inlet fluid to a turbineimpeller.

According to the general features of the present invention, a housing isprovided having a nozzle block portion with a plurality of nozzle inletsarranged to expand a fluid in the direction of a rotatable impellercarried on a shaft journaled in said housing. An air gap is providedbetween the impeller and the housing and a valve or other areacontrolling device, for example, a valve having a plurality ofthrottling apertures corresponding in number and size to the nozzleinlets, is movably mounted in the air gap so that the throttlingapertures may be moved into and out of registry with the nozzle inlets,thereby to control the flow of fluid from the inlets to the impeller.

Torque-producing means responsive to the rotation of the impeller areconnected to the rotary valve to control positioning of the valve uponrotation of the impeller, thereby to impart a torque to the valve bymeans of which the positioning of the throttle apertures may beregulated.

It is an object of the present invention to provide a turbineconstruction wherein the effective throat area of a nozzle inlet may becontrolled by a throttling member which is directly responsive to avariable condition.

Another object of the present invention is to provide a turbineconstruction having a rotary valve or other area controlling memberarranged to throttle inlet air to the turbine in response to actuationby condition sensitive 11168115.

A further object of the present invention is to provide a rotary valvefor a turbine construction wherein the valve comprises the rotor of aneddy current device by means of which the positioning of the valve maybe selectively controlled.

Yet another object of the present invention is to provide a rotary valvefor a turbine construction adapted to have a torque imparted thereto inresponse to the speed of rotation of the turbine impeller.

A further object of the present invention is to provide a new andimproved eddy current throttle.

Many other features, advantages and additional objects of the presentinvention will become manifest to those versed in the art upon makingreference to the detailed description which follows and the accompanyingsheets of drawings in which a preferred embodiment of a structureincorporating the principles of my invention is shown.

On the drawings:

Figure 1 is a cross-sectional view with parts shown in elevation showingone structural embodiment of a turbine construction incorporating theprinciples of the present invention;

Figure 2 is an enlarged fragmentary cross-sectional view takensubstantially on line IIII of Figure 1;

Figure 3 is an enlarged fragmentary elevational view looking through oneof the nozzle inlets and showing the rotary valve of the presentinvention positioned so as to provide a fully open port; and

hired States Patent 2,935,295 Patented May 3, 1960 'ice Figure 4 is aview similar to Figure 3, but showing the rotary valve of the presentinvention positioned to partially restrict the nozzle inlet port.

As shown on the drawings:

Although the principles of the present invention find a particularapplicability to a turbine construction, it will be understood that I donot wish to be limited to the specific environment herein described byway of illustrative ex ample only.

The improved throttling arrangement of the present in-- vention is shownin connection with a turbine construction indicated generally by thereference numeral 10 and includes a housing 11 having an impellerchamber 12 and an annular nozzle block 13 in which is formed a pluralityof spaced nozzle inlets 14 arranged to expand and direct a fluid towardthe vane elements 16 of an impeller 17 keyed as at 18 to a shaft 19journaled for rotation in a bearing means 20 mounted in the housing 11.

The housing 11 is formed with an internal annular recess 21concentrically disposed relative to a hub portion 22. The impellerchamber 12 of the housing 11 is also constructed to provide asubstantially annular air gap 23 between the impeller 17 and the inletside of the housing 11.

A rotary valve 24 is mounted for movement in the air gap 23 and includesan axially extending annular flange 25 which is arranged to encircle thehub 22 in the locale of the recess 21, an annular bearing 26 beingcarried by the housing 11 so as to journal the valve 24 for movement inthe air gap 23.

It will be noted that the air gap 23 extends radially to the nozzleinlets 14 and the valve 24 is provided with a control portion 27 havinga plurality of throttling apertures 28 corresponding in number with thenozzle inlets 14 and arranged to be moved into and out of registry withthe nozzle inlets 14, thereby to selectively restrict the effective areaof opening of the nozzle inlets 14 and thereby to control the flow offluid from the nozzle inlets 14 to the vane elements 16 of the impeller17.

It will be understood that the throttling apertures 28 by way ofexemplification of the present inventive principles are preferably ofthe same size as that portion of theof a torsion spring 29 having oneend thereof operatively connected to the housing 11 and the other endthereof operatively connected to the flange 25 of the rotary valve 24.

It will be apparent that the flow of fluid from the nozzle inlets 14 tothe vane elements 16 of the impeller 17 will be at a maximum when thethrottling apertures 28 are in full open registry with the nozzle inlet14 as shown in Figure 3. To cut down the flow of fluid, the rotary valve24 is rotated selectively so as to move the throttling apertures 23 outof registry with the nozzle inlet 14 a shown in Figure 4.

In order to impart the necessary torque to the rotary valve 24, thepresent invention contemplates the provision of a condition sensitivecontrol device to position the rotary disc-type valve 24, for example,by imparting a torque tending to move the valve in response to therotational speed of the impeller 17.

Because the rotary valve 24 is generally disc-shaped and develops athrottling function, the relationship thereof to the inventive subjectmatter is sometimes identified herein by use of the terms disc andthrottle member as well as the term control valve.

The torque-producing means may, by way of example, take the form of atleast a pair of bar magnets indicated at 30 and 31. The magnet 30 isshown with its north pole arranged directly adjacent the air gap 23 andthe magnet 31 is shown with itssouth pole similarly situated but spacedapart from the magnet 30. A washer 32. of paramagnetic material bridgesthe opposite ends of the magnets 30 and 31 and also serves to engage anut 33 threaded on the end of the shaft 19 to hold the impeller 17 inassembly therewith.

In order to promote a full flux flow through the air gap 23 in thevicinity of the rotary valve 24, a washer 34 made of paramagneticmaterial may be carried by the shaft 19 on the housing side of therotary valve 24, thereby completing a magnetic circuit through the airgap 23.

In order to minimize flux leakage, the shaft 19 is preferably made ofnon-magnetic material.

In operation, the magnetic lines of flux produced by the magnets 30 and31 pass through the disc-type rotary valve 24. Upon rotation of theimpeller 17 changing flux linkages result in portions of the disc-typevalve 24 in proximity to the magnets 30 and 31 and an electrometiveforce is generated which, in turn, causes eddy currents to flow in thevalve 24. The eddy currents, in establishing their own magnetic fieldswhich interact with the fields of the magnets 30 and 31, impart a torqueto the rotary valve 24, thereby tending to move the control portion 27of the valve 24 so as to control the flow of fluid through the nozzleinlets 14, to the vane elements 16 of the impeller 17.

It may be noted that the torque imparted to the rotary valve 24 will, inaccordance with well known physical relationships, be related in apredetermined proportion to the speed of rotation of the impeller 17.Thus, the rotary valve 24 can be eifectively employed to throttle theinlet fluid flow to the turbine impeller 17.

It will be understood, of course, that flux producing means carried bythe impeller 17 is particularly characterized by being capable ofestablishing a flux pattern in the air gap 23 so that the torqueimparted to the rotary valve 24 could be controlled as a function of therotational speed of the impeller 17.

The mounting of the rotary valve 24 for rotation in dependent of therotation of the impeller 17 makes it feasible to apply a torque to therotary valve 24. Accordingly the speed responsive eddy current deviceherein described by way of a preferred embodiment is merely exemplary ofone form of actuating mechanism responsive to such dififerent variablefactors involved in the operation of the turbine as pressure, flowvolume, temperature, or any other measurable quantity.

Although various minor structural modifications might be suggested bythose versed in the art to the preferred embodiment herein described ingreat detail for the sake of clarity only, it should be understood thatI wish to embodywithin the scope of this patent all such modificationsas reasonably and properly come Within the scope of my contribution tothe art.

I claim as my invention: 7

1. In a turbine construction, a'housing, a shaft journaled for rotationtherein, an impeller carried by said shaft for rotation in said housing,said housing having an annular nozzle block portion forming an annularrow of nozzle inlets arranged to expand a fluid toward said impeller torotatably drive said impeller, said impeller and said housing togetherwith one another forming an annular air gap therebetween extending tosaid nozzle inlets, a rotary valve journaled in said housing forrotation in said air gap, said valve having an annular control portionin said air gap with an annular row of openings therein corresponding innumber to said plurality of nozzle inlets and being so selectively movedinto and out of register with said inlets to restrict the flow of fluidfrom said nozzles to said impeller upon relative movement of said valvewith'respect to said housing, a control spring operatively connectedbetween said housing and said valve 4 to load said valve in apredetermined angular direction and magnetic .eddy currenttorque-producing means between said valve and said impeller to impart aturning torque to said valve in response to rotation of said impeller toovercome said control spring for controlling the effective area of saidnozzle inlets.

2. In a turbine construction, a housing, a shaft journaled for rotationtherein, an impeller carried by said shaft for rotation in said housing,said housing having an annular nozzle block portion forming a pluralityof nozzle inlets arranged to expand a fluid toward said impeller torotatably drive said impeller, said impeller and said housing togetherwith one another forming an annular air gap therebteween extending tosaid nozzle inlets, a disc made of paramagnetic material carried by.said housing for movement in said air gap, said disc having a controlportion with an annular row of openings therein corresponding in numberto said plurality of nozzle inlets and being moved into and out ofregister with said inlets to selectively restrict the flow of fluid fromsaid nozzles to said impeller upon relative movement of said disc withrespect to said housing, a control spring operatively connected betweensaid housing and said disc to load said disc in a predetermined angulardirection and magnetic flux-producing means carried by said impeller andarranged to induce eddy currents in said disc, thereby to impart aturning torque to said disc in response to rotation of said impeller toovercome said control spring for controlling the effective area of saidnozzle inlets.

3. In a turbine construction, a housing, a shaft journaled for rotationtherein, an impeller carried by said shaft for rotation in said housing,said housing having an annular nozzle block portion forming a pluralityof nozzle inlets arranged to expand a fluid toward said impeller torotatably drive said impeller, said impeller and said housing togetherwith one another forming an annular air gap therebetween extending tosaid nozzle inlets, a disc made of paramagnetic material carried by saidhousing for movement in said air gap, said disc having a control portionwith a plurality of openings therein corresponding in number to saidplurality of nozzle inlets and cooperating therewith to provide aplurality of variably sized flow passages through said air gap toselectively restrict the flow of fluid from said nozzles to saidimpeller upon relative movement of said disc with respect to saidhousing, a control spring operatively connected between said housing andsaid disc to load said disc in a predetermined angular direction andmagnetic flux-producing means carried by. said impeller and arranged toinduce eddy currents in said disc, thereby to impart a turning torque tosaid disc in response to rotation of said impeller to overcome saidcontrol spring for controlling the eflective area of said nozzle inlets,said magnetic flux-producing means including at least a pair of barmagnets carried by said impeller with opposite poles arrangedadjacentsaid air gap.

journaled for rotation therein, an impeller carried by said shaft forrotation in said housing, said housing having an annular nozzle blockportion forming a plurality of nozzle inlets arranged to expand a fluidtoward said impeller to rotatably drive saidrimpeller, said impeller andsaid housing together with one another forming an annular air gaptherebetween extending to said nozzle inlets, a disc made ofparamagnetic material carried by said housing for movement in said airgap, said disc having a control portion comprising an offset flanged rimwith a plurality of openings therein corresponding in number to saidplurality of nozzle inlets and arranged to selectively restrict the flowof fluid from said nozzles to said impeller upon relative movement ofsaid disc with respect to saidvhousing, a control spring operativelyconnected between said housing and said disc to load said disc in apredetermined direction and magnetic flux-producing means carried bysaid impeller and arranged to induce eddy currents in said disc, therebyto impart a turning torque to said disc in response to rotation of saidimpeller to overcome said control spring for controlling the effectivearea of said nozzle inlets, a washer of paramagnetic material on saidshaft on one side of said disc and at least a pair of bar magnetscarried by said impeller with opposite poles spaced apart from oneanother and arranged adjacent said air gap on the other side of saiddisc.

5. In a turbine construction, a housing, a shaft journaled for rotationtherein, an impeller carried by said shaft for rotation in said housing,said housing having an annular nozzle block portion forming a pluralityof nozzle inlets arranged to expand a fluid toward said impeller torotatably drive said impeller, said impeller and said housing togetherwith one another forming an annular air gap therebetween extending tosaid nozzle inlets, a disc made of paramagnetic material carried by saidhousing for movement in said air gap, said disc having a control portioncomprising a flange with a plurality of openings therein correspondingin number to said plurality of nozzle inlets and arranged to selectivelyrestrict the flow of fluid from said nozzles to said impeller uponrelative movement of said disc with respect to said housing, a

control spring operatively connected between said housing and said discto load said disc in a predetermined direction and magneticflux-producing means carried by said impeller and arranged to induceeddy currents in said disc, thereby to impart a turning torque to saiddisc in response to rotation of said impeller to overcome said controlspring for controlling the eflective area of said nozzle inlets, awasher of paramagnetic material on said shaft on one side of said discand at least a pair of bar magnets carried by said impeller withopposite poles spaced apart from one another and arranged adjacent saidair gap on the other side of said disc, and a washer of paramagneticmaterial bridging the opposite ends of said bar magnets, thereby tocomplete a closed magnetic circuit through said air gap.

6. In a turbine construction, a housing, a shaft j urnaled for rotationtherein, an impeller carried by said shaft for rotation in said housing,said housing having an annular nozzle block portion forming a pluralityof nozzle inlets arranged to expand a fluid toward said impeller torotatably drive said impeller, said impeller and said housing togetherwith one another forming an annular air gap therebetween extending tosaid nozzle inlets, a disc made of paramagnetic material carried by saidhousing for movement in said air gap, said disc having a control portionwith a plurality of openings therein corresponding in number to saidplurality of nozzle inlets and arranged to selectively restrict the flowof fluid from said nozzles to said impeller upon relative movement ofsaid disc with respect to said housing, a control spring operativelyconnected between said housing and said disc to load said disc in apredetermined direction and magnetic fluxproducing means carried by saidimpeller and arranged to induce eddy currents in said disc, thereby toimpart a turning torque to said disc in response to rotation of saidimpeller to overcome said control spring for controlling the effectivearea of said nozzle inlets, a washer of paramagnetic material on saidshaft on one side of said disc and at least a pair of bar magnetscarried by said impeller with opposite poles spaced apart from oneanother and arranged adjacent said air gap on the other side of saiddisc, and a washer of paramagnetic material bridging the opposite endsof said bar magnets, thereby to complete a closed magnetic circuitthrough said air gap, said shaft being of nonmagnetic material, therebyto minimize flux leakage.

7. In a turbine construction, a housing, bearing means therein, a shaftjournaled for rotation in said bearing means, an impeller carried bysaid shaft and rotatable in said housing, said housing having an annularrow of nozzles arranged to expand a fluid toward said impeller, therebyto rotatably drive said impeller, a throttle member mounted in saidhousing for rotation independent of said impeller and having a controlportion formed with an annular row of apertures arranged to be movedinto and cut of register with said nozzles .to selectively control theflow of driving fluid to said impeller, control means normally biasingsaid throttle member in one angular direction with said nozzles and saidapertures in full open register, and condition-sensitive means to movesaid throttle relative to said nozzles to restrict flow through saidnozzles in response to variations from a reference condition, saidcondition-sensitive means comprising an eddy current device wherein saidthrottle member comprises a rotatable valve of paramagnetic material andmagnetic flux-producing means carried by said shaft and said impeller ininductive relationship with said throttle member, thereby to impart aturning torque to said throttle member, the quantitative value of saidtorque being proportional to the speed of rotation of the impeller.

8. In a turbine construction, a housing, bearing means therein, a shaftjournaled for rotation in said bearing means, an impeller carried bysaid shaft and rotatable in said housing, said housing having an annularrow of nozzles arranged to expand a fluid toward said impeller, therebyto rotatably drive said impeller, a throttle member mounted in saidhousing for rotation independent of said impeller and having a controlportion formed with an annular row of apertures complementary to saidnozzles and arranged to be moved into and out of register with saidnozzles to selectively control the flow of driving fluid to saidimpeller, control means normally biasing said throttle member in oneangular direction with said nozzles and said apertures in full openregister, and condition-sensitive means to move said throttle memberrelative to said nozzles to restrict flow through said nozzles inresponse to variations from a reference condition comprising an eddycurrent device wherein said throttle member consists of a rotatable discvalve of paramagnetic material and said shaft and said impeller carrymagnetic flux-producing means in inductive relationship with saidthrottle member to impart a turning torque to said throttle memberproportional in quantitative value to the speed of rotation of theimpeller, said shaft being made of a non-magnetic material to minimizeflux leakage.

9. A turbine construction comprising in combination, a housing, a rotormounted for rotation in the housing and provided with circumferentiallyspaced vane elements, a fixed nozzle member adjacent said vane elementsand through which motive fluid is supplied to the vane elements, anannular throttling member between the fixed nozzle member and the vaneelements and having spaced openings therein, bearing means supportingthe throttling member so that the throttling member is capable ofcontinuous angular adjustment between a first position in which themotive fluid can freely flow therethrough to the vane elements and asecond position in which all of the motive fluid is deflected by thethrottling member away from the vane elements, torqueapplying meansdriven by the rotor and operatively connected between said rotor andsaid throttling member to adjust said throttling member in angulardirection as a function of the speed of rotation of the rotor so thatthe throttling member is angularly displaced by the said torque-applyingmeans into positions of adjustment between said first and secondpositions for deflecting the motive fluid away from the vane elements asa function of the speed of the rotor, and spring means interconnectingthe housing and the throttling member and applying a continuous biasingforce urging the throttling member into its first position, saidtorque-applying means comprising an eddy current device and saidthrottling member consisting of a rotatable disk valve of conductive 7f8 7 matrial, and said eddy current device mm'e particularly 2,364,810Nti'fnim Dec. 12, 1944 including magnetic flux-producing means rotatablydriven 2,459,519 Graham et a-l. Jan. 18, 1949 by the rotor in inductiverelation to said throttling mem- 2,559,006 Clapham July 3,-1951 bar forthe purposes set forth. 2,569,898 Millns Oct. 2, 1951 v I =5 2,733,891Milins Feb. 7', 1956 References Cited in the file of this patent VUNITED STATES PATENTS FOREIGN PATENTS 2,154,572 Lansing Apr. 18, 1939-91,931 Germany May '31, 1897 2,292,090 Reichel Aug. 4, 1942 918,317France Oct. 14, 1946

